1. Field of the Invention
The invention relates to an electronic device, and more particularly, to a power amplifier.
2. Description of the Related Art
A conventional power amplifier generally uses a transistor cascode constructed from two transistors connected in series for realization in view of stability and frequency responses. However, in an advanced manufacturing process, a conventional cascade power amplifier faces a problem that a voltage shift occurs at connection nodes of the transistor cascode, causing the voltages of output differential signal to shift as well. It is hard to meet the reliability requirement of transistor devices.
Accordingly, what is needed is a power amplifier with a more than two-stage cascade configuration to address the above-identified problems. The invention addresses such a need.